First Volendam trip we discovered that we could "Pre-order" wine at a discount (10%) and found that to be a good bargain; we got our beaujolais for $22 or so.
Next trip, not only was the pre-order concept gone, but after the first night, so was the beaujolais. BUT, we discovered that on the Lido deck wine by the bottle was much cheaper than in the dining room, so we did use that for nights we ate in the room.
I must add that every time we brought wine from our room to the dining room we were charged the $15 corking fee (both trips) despite the fact that we were in a deluxe suite. I found that unconscionable, especially when they ran out of "our" wine so early in the trip.